Elaine Gardner, British Dietetic Association (BDA) Spokesperson, presents part 1 in our brand new series of columns on sugar and sugar alternatives.
What is it? A polyol (sugar alcohol) that looks and tastes like sugar (can be used in equal measurement).
Found in? Available to purchase in granular form and in a range of specialist food products like honey, jams and chocolate. Medications and oral health products (mouth rinses, toothpaste, lozenges) can contain xylitol. It is found naturally in very small amounts in some fruits like berries, but the most common source of xylitol is from sugar-free chewing gum.
Effect on general health: Xylitol has a lesser effect on blood sugar levels than sugar, due to its slow absorption rate (low glycaemic index of 7). It can be useful as an alternative to reduce sugar consumption for people with diabetes as it does not raise blood glucose or insulin levels.
It has a reduced caloric value which can be helpful in weight control. One spoon of sugar contains 16 calories versus 10 calories from xylitol. This is a small saving, but not very much.
Xylitol is slowly and only partially absorbed in the intestine and too much can cause water retention, resulting in diarrhoea. It is not recommended to consume more than 50 g xylitol per day.
Oral health impact: Xylitol is not metabolised by bacteria in the mouth and so it does not contribute to tooth decay. It also helps remineralise tooth enamel.
Chewing sugar-free gum stimulates the flow of saliva through the chewing action; stimulated saliva helps to reduce acidity in the mouth by washing away plaque acids and contributes to their neutralisation by providing an important buffer, bicarbonate. Stimulation of saliva flow through the use of sugar-free gum results in a 10–12-fold increase over a resting saliva rate, which helps wash away debris of food particles and sugars from the mouth and restore optimum pH levels in the mouth faster than without sugar-free gum.
Saliva also has an important role in the maintenance of tooth mineralisation as it provides the calcium and phosphate ions used to repair damaged enamel and it encourages the remineralisation of early caries.
Chewing gum sweetened with xylitol also helps reduce oral Streptococcus mutans levels, a key pathogen responsible for dental caries.
Advice for patients: Xylitol is a useful alternative to sugar but moderation in the quantity consumed is important.
Sugar-free chewing gums using xylitol are a convenient, simple and effective means of improving dental health through the stimulation of saliva when used regularly throughout the day.
Find out more about the British Dietetic Association at: www.bda.uk.com .
Milgrom P, Ly K, Rothen M . Research findings on xylitol and the development of xylitol vehicles to address public health needs. Adv Dent Res 2009; 21: 10.1177/0895937409335623.
Söderling E. Controversies around xylitol. Eur J Dent 2009; 3: 81–82.